Hepatic neoplasms with cystic features are rare .
The imaging finding of a pseudocystic lesion of the liver, in absence of clinical symptoms, implies several differential diagnoses, ranging from infectious diseases such as echinococcal cysts , benign lesions as simple biliary cysts and biliary cystadenomas, up to primary or metastatic malignancies.
Two cases of pseudocystic GEP/NETs liver metastases [12, 13] and two primary hepatic pseudocystic NETs [16, 17] have been described.
However, this is the first case of a G1 NET that provoked pseudocystic hepatic metastasis. Hepatic pseudocystic secondarisms are also reported from uterine cervical carcinoma , spinal haemangiopericytoma  and nasopharyngeal carcinoma .
Neuroendocrine tumors can undergo pseudocystic metastases in different sites: a cerebral cystic metastasis of neuroendocrine carcinoma, with unknown primary tumor, has been reported .
Cystic changes are often reported in liver malignancies after a neo-adjuvant treatment. This is thought to be due to therapy-induced tumor necrosis .
A pseudocystic appearance with a peculiar peripheral contrast enhancement are described in pancreatic NETs  and in a case of a case of primary micro-neuroendocrine tumor arising in a horseshoe kidney .
Primary cystic NETs display a less frequent tendency to undergo nodal and hepatic spread when compared to solid counterparts.
We observed an aggressive behaviour, with multiple hepatic and nodal metastases in a well differentiated (G1) ileal NET at the time of diagnosis.
In our case, once the neuroendocrine nature of the primary ileal mass was histologically confirmed, the 111In-pentetreotide somatostatin receptor scintigraphy revealed the same capitation pattern in the hepatic cyst, suggesting its secondary nature. Taking account on these acknowledgements, a complete resection of the cyst was performed. Neo-adjuvant chemotherapy was not performed, despite the advanced clinical stage .
Both macroscopic and microscopic examination showed that the pseudocystic appearance of this metastasis was not due to the central necrosis, but to intratumoral haemorrhage.
All the described findings were incidental, and patient did not complain for pain, flushing, diarrhea or other symptoms related to a ‘’hypersecretion syndrome”. For this reason, the hepatic pseudocyst could have been misdiagnosed, unless an ileal mass was identificated and raised the suspicion for a metastatic NET.
A complete resection of NET hepatic metastases leads to an improved prognostic outcome: 5-years overall survival rates higher than 70%  are reported, despite recurrences develop in up to 80% of patients . Thus, the rationale to remove NET liver metastases, once technically feasible, is established. In order to either obtain an accurate pre-treatment assessment and plan an adequate surgical strategy, it is crucial to differentiate liver NET metastases from other primary or secondary hepatic malignancies (that may not take advantage of the similar prognostic improvements), as well as from benign lesions. For these reasons, we recommend to keep in consideration unusual NET presentations, such as the described one.